bt829bkrf ETC-unknow, bt829bkrf Datasheet - Page 50

• Manufacturer Part Number: bt829bkrf
• Description: Video Streamii Decoders
• Manufacturer: ETC-unknow

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1.0 Functional Description
1.9 Bt829B VBI Data Output Interface
1.9.5 VBI Frame Output Mode
In VBI frame output mode, the Bt829B is generating VBI data all the time (i.e.,
there is no VBI active interval). In essence, the Bt829B is acting as an ADC
continuously sampling the entire video signal at 8*Fsc. The Bt829B generates
HRESET,VRESET and FIELD timing signals in addition to the VBI data, but the
DVALID, HACTIVE, and VACTIVE signals are all held high during VBI frame
output operation. The behavior of the HRESET,VRESET, and FIELD timing
signals is the same as normal YCrCb 4:2:2 output operation. The
HRESET,VRESET, and FIELD timing signals can be used by the video processor
to detect the beginning of a video frame/field, at which point it can start to capture
a full frame/field of VBI data.
on the stability of the analog composite video signal input to the Bt829B. The
Bt829B will generate 910 16-bit VBI data words for NTSC and 1,135 16-bit VBI
data words for PAL/SECAM for each line of analog video input at a CLKx1 rate,
assuming a nominal or ideal video input signal (i.e., analog video signal has a sta-
ble horizontal time base). This is also equivalent to 1,820 8-bit VBI data samples
for NTSC and, 270 8-bit VBI data samples for PAL/SECAM for each line of ana-
log video input. These values can deviate from the nominal depending on the
actual line length of the analog video signal.
ter. The output byte ordering may be controlled by the VBIFMT bit as described
for VBI line output mode. If both VBI line output and VBI frame output modes
are enabled at the same time, the VBI frame output mode takes precedence. The
VBI data range in VBI frame output mode can be controlled using the RANGE
bit in the OFORM register, and a video signal must be present on the Bt829B ana-
log input for this mode to operate as defined by the status of the VPRES bit in the
STATUS register (0x00).
The number of VBI data samples generated on each line may vary depending
VBI frame output mode is enabled via the VBIFRM bit in the OFORM regis-
D829BDSA
VideoStream II Decoders
Bt829B/827B